1. Field of the Invention
The present invention relates to a paper sheet processing apparatus which aligns a paper sheet supplied to a tray in a stacked state, and a paper sheet processing method.
2. Description of the Related Art
There is a conventional paper sheet post-processing apparatus having a sheet stock unit provided with a paddle in a conveying path to lead a paper sheet to a processing tray to stack a plurality of paper sheet and to staple the stacked paper sheets (e.g., Jpn Pat. Appln. KOKAI Publication No. 2001-171889, Summary, FIG. 7-FIG. 15). This sheet stock unit functions to hold a plurality of paper sheet until the stapling in the processing tray is finished.
In the above apparatus, whenever a paper sheet is stocked in the sheet stock unit, the paddle is rotated to press down the rear end of the paper sheet in the conveying direction to prevent interference with a next paper sheet supplied to the sheet stock unit. Therefore, when stocking two or more paper sheets, a previously stacked sheet is prevented from being collided with a next supplied paper, and two or more paper sheets can be stocked in an orderly stacked state.
However, in the above conventional paper sheet post-processing apparatus, since the paddle is rotated by 180° and the rear end of the paper sheet is bent down just like being tapped by the paddle each time a paper sheet is supplied to the sheet stock unit, a relative large noise is generated. Further, since the sheet rear end is forcibly bent downward from the conveying path each time a paper sheet is stacked, the rear end of the paper sheet is curled when a stocked paper sheets are supplied to the processing tray, causing a problem of disturbing the stacked state.